Outlook reminders duplicate upgrade exchange 2007 to exchange 2013

I have some users who upgraded from Exchange 2007 to exchange 2013. For some reason their reminders (well some of them) have duplicated itself. The users are in online mode and I had them to go to OWA. When they logged into Owa THEYconfirmed the same duplicates. I had the user to close outlook and do outlook.exe /cleanreminders and they have the same problem. The users using  Outlook 2010 sp2.
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Clark KentSoftware Engineer cum BloggerCommented:
Hi Techdrive,

I think, you should take help of MFCMAPI to clear all the duplicate appointments (while connected with Exchange). As it is handy task, read the given tutorial which is based on How to Delete Reminders?

Source: ttp://www.slipstick.com/outlook/calendar/delete-reminders-that-keep-returning/

Feel free to respond back for further assistance!!

Clark Kent

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